Prescription farming is described in U.S. Pat. No. 6,122,581 which issued Sep. 19, 2000, to McQuinn entitled Multi-Variable Rate Dispensing System for Agricultural Machine. As stated by McQuinn, there is a need for a variable rate applicator system for controlling delivery of agricultural products, also referred to by McQuinn as crop inputs, being dispensed from dispensing points across a spreader boom, planter, seeder and various other applicator devices substantially transverse to their direction of travel so as to accurately and precisely dispense agricultural products individually from multiple dispensing points attached to the applicator machine as the machine traverses a desired product delivery area. McQuinn notes that significant changes in soil conditions, topographical features, and/or characteristics such as nutrient levels, soil compaction, drainage or other qualifying crop production characteristics, have been found to occur even within a distance of a few feet. McQuinn describes simultaneously controlling the prescription and quantity of multiple agricultural products dispensed from multiple dispensing points attached to a variable rate product applicator machine so as to provide a multi-variable rate dispensing system wherein a digital map is used to coordinate the system. The map is customized to apply agricultural products to a desired target area being traversed by the application machine regardless of crop input prescription and quantity requirement differences at individual dispensing point locations across the machine. A computerized control system is described which holds a digital map of the location of various soil types, topographical features, and/or characteristics such as nutrient levels, soil compaction, drainage or other qualifying crop production characteristic in the field to be treated, and is responsive to machine locating devices such as GPS receivers for determining the location of the machine in the field, looking up the soil type, topographical features, and/or qualifying crop production characteristics of the soil the machine is currently over based upon its location, and simultaneously adjusting the crop input prescription and quantity for each individual dispensing point in response thereto.
McQuinn describes the map coordinated system as allowing for variable input control in the horizontal plane from one side to the other, either by section control wherein several dispensing points are grouped together, or through individual dispensing point control. McQuinn states that, when utilized for planting or seeding applications, it may also be necessary to instruct different points on the machine to dispense different varieties of seeds and/or vary the rate of seeds to be dispensed therefrom so as to control the rates and or varieties of the seeds dispensed from the machine in a direction that is transverse to the direction of machine travel. McQuinn continues, stating that controlling these variable delivery rate differences is necessary when crop inputs are simultaneously dispensed from different dispensing points on the application machine, each delivering a unique and distinct prescription and quantity of crop inputs in response to the computerized control system which holds the digital soil map of the location of various soil types, topographical features, and/or any qualifying crop production characteristics in the field to be treated.
McQuinn states that the application of any product to be dispensed is matched with the crop input prescription and quantity requirements for the field reference point unique to each respective dispensing point or group of dispensing points. McQuinn further states that the rate and prescription of crop inputs dispensed from each respective dispensing point is adjusted so that each crop input is dispensed for a specific target area of predetermined conditions, all based upon formerly measured conditions and values for that certain target area. McQuinn describes that crop inputs are determined by the application machine operator and may include products such as herbicides, insecticides, fertilizer, and various chemicals, and may also include or be limited to seeds exclusively to accommodate planter control. McQuinn describes using data processors to extract prescription and quantity data which has been programmed into a software database. McQuinn describes that database information also includes that which is specific to the applicator machine and includes the type and location of each dispensing point or group of dispensing points, giving the examples of spray nozzles, spreading wheels, injection tubes, and associated actuators. McQuinn states that his multi-variable rate dispensing system is adaptable for use with dry boom systems, or combinations of dry boom systems and wet boom systems, as well as planters, drills, spinners, drop tubes, injectors, etcetera.
Applicant is also aware of U.S. Pat. No. 5,931,882, to Fick which issued Aug. 3, 1999, for a Combination Grid Recipe and Depth Control System. Fick describes a multi-product application system, seed planting system and control for the dispensing of liquid or granular products in pre-selected amounts and planting seeds at pre-selected depths and frequencies, where three or more separate products can be dispensed simultaneously and wherein the seed planting depth can be varied. A grid recipe system defines the amounts of each type of product to be applied to specific areas of the field and/or which defines seed planting depths and frequencies for specific areas of the field. GPS and the recipe data is processed by a computer. The recipe and/or depth/frequency grid is created by the farmer based on personal knowledge and experience. Fick describes that the products being dispensed may be fertilizers, herbicides, insecticides, fumigants, carriers, seeds or other similar materials which are applied in either liquid or granular form. He states that the term recipe is intended to encompass chemical recipes, dispense rates, as well as seed planting depths and frequencies, and that the control system uses GPS to provide the location of the product applicator.
Fick describes that five separate product containers may contain five different types of products which may be applied simultaneously via a single manifold feeding an in-line mixing device used to thoroughly mix the flow, from which the flow is directed out through controlled valves to the booms and dispensing nozzles. Fick states that the depth control unit may be driven mechanically, electrically or hydraulically.